Confectionery shells provide a structurally firm outer in which confectionery fillings can be placed and are a well-known aspect of confectionery manufacture. A confectionery shell may also serve as a matrix in which pieces of edible material are dispersed. These inclusions have a different composition to that of the confectionery shell. Confectionery shells having a multi-layered structure are also known. The layers of the shell may differ in terms of their composition and/or colour.
It is known to manufacture a confectionery shell by depositing shell material into a mould cavity, vibrating the mould to remove air bubbles in the material and inverting the mould to remove excess material (“inversion method”). However, this method suffers from the disadvantage that the excess material must be collected and treated (e.g. re-tempering of chocolate) to avoid wastage. Also, the shell typically does not have a uniform thickness, especially when using a shell material having a relatively high viscosity. This imposes restrictions on the composition (e.g. fat content) of the material.
An improved method for manufacturing a confectionery shell involves immersing a chilled stamp into the shell material in a mould cavity to shape and solidify the material against the wall of the cavity (“cold-stamping”). This produces a shell having a uniform thickness and does not produce as much excess material as the inversion method. Furthermore, cold-stamping is not as dependent on the viscosity of the shell material.
For instance, US-A-2006/0057265 describes a cold-stamping process in which the substance forming the confectionery shell is placed under pressure after the stamp is introduced into the mould. The process uses a stamp having an axial bore through which pressure is exerted by means of a pressure-transmitting medium.
US-A-2006/0257517 concerns a cold-stamping process in which the stamp has a flange that covers the mould boundary. The flange is fitted with a deformable toroid sealing means which serves to enclose the substance forming the confectionery shell once the stamp is placed in the mould.
However, producing confectionery shells of a defined thickness by conventional cold-stamping technology requires accurate stamps and moulds. If the stamps and moulds are not accurately dimensioned, the cavity formed between the mould and the stamp is ill-defined and the ensuing confectionery shell can have a less than satisfactory appearance. In some circumstances, which can depend upon product type and intended consumer, confectionery shells produced with an ill-defined cavity can be of unacceptable quality. This limitation means that a mould/stamp combination designed for producing one shell thickness cannot be used to produce another thickness of shell without having a detrimental effect on product quality. Producing a new thickness of confectionery shell therefore requires a new set of well-designed and precision-manufactured moulds and stamps.
The commissioning and manufacture of each set of stamps and moulds is expensive and results in a time delay before a new thickness of confectionery shell can be produced of acceptable quality. Even when the required stamps and moulds are already available, installing these stamps and moulds halts production and is therefore also not cost-effective.
The need for accurate stamps and moulds also has implications when producing multi-layer confectionery shells. This is because each ensuing layer in a multi-layer structure has the effect of increasing the thickness of the overall multi-layer shell. Accurate stamps and moulds are typically needed to produce each new thickness of the overall multi-layer shell.
It is therefore an object of the present invention to overcome these limitations and provide methods for the manufacture of confectionery shells which are less reliant upon accurate, tailor-made stamps and moulds.